Re: Hardware/OS recommendations for large databases (

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Luke Lonergan wrote:
Mark,

On 11/18/05 3:46 PM, "Mark Kirkwood" <markir@xxxxxxxxxxxxxxx> wrote:
If you alter this to involve more complex joins (e.g 4. way star) and
(maybe add a small number of concurrent executors too) - is it still the
case?


4-way star, same result, that's part of my point.  With Bizgres MPP, the
4-way star uses 4 concurrent scanners, though not all are active all the
time.  And that's per segment instance - we normally use one segment
instance per CPU, so our concurrency is NCPUs plus some.


Luke - I don't think I was clear enough about what I was asking, sorry.

I added the more "complex joins" comment because:

- I am happy that seqscan is cpu bound after ~110M/s (It's cpu bound on my old P3 system even earlier than that....) - I am curious if the *other* access methods (indexscan, nested loop, hash, merge, bitmap) also suffer then same fate.

I'm guessing from your comment that you have tested this too, but I think its worth clarifying!

With respect to Bizgres MPP, scan parallelism is a great addition... very nice! (BTW - is that in 0.8, or are we talking a new product variant?)

regards

Mark



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